Element Patterns Research Articles

Early Ediacaran Xueqiong ophiolite in the East Kunlun Orogen, northern Tibetan Plateau: Insights into the early evolution of the Proto-Tethys Ocean

Reshaping the tectonic evolution of the Proto-Tethys Ocean is of paramount significance for comprehending the ocean-continent transitions since the Neoproterozoic. Nevertheless, the intricacies of this evolution, particularly during its early stage, remain a pivotal issue that needs further deciphering. The discovery of early Ediacaran ophiolites within the East Kunlun Orogen offers a crucial clue for exploring this issue. This study presents intergrade field geology, zircon U–Pb geochronology and whole-rock geochemistry on the related rocks from this specific ophiolite identified in the Xueqiong area, easternmost East Kunlun Orogen. Field investigations reveal the currently remaining dismembered Xueqiong ophiolite merely include gabbro, basalt and chert, which are in the form of tectonic blocks within an ophiolitic mélange. Zircon U–Pb dating results show that the gabbro samples from two near rock slices yield consistent weighted mean ages of 597 ± 5 Ma and 601 ± 2 Ma, whereas the basalt sample gives a similar age of 600 ± 6 Ma as well, indicating the magmatic component of the ophiolitic suite was formed at ca. 600 Ma during the early Ediacaran. Geochemical analysis indicates that all the gabbro and basalt share a common parental magma. Patterns of rare earth and trace elements show their properties between the enriched mid-ocean ridge basalt and oceanic island basalt models, along with their characteristic trace element covariances aligning with enriched mid-ocean ridge basalt, suggesting a mantle source similar to the enriched mid-ocean ridge basalt, with interaction with the residual asthenosphere mantle material. Relatively low SiO2, TFe2O3 and MnO2 contents and flat rare earth element patterns of chert, suggesting its lithogenic property and restricted basin setting near the continental margin. These findings collectively indicate that the Xueqiong ophiolite represents remnants of the oceanic lithosphere and overlying deep-sea sediments from the early-stage evolution of the Proto-Tethys Ocean, when the ocean evolution might not have been fully mature and oceanic floor sedimentation capable of receiving terrigenous detritus. This evidence further supports that the Proto-Tethys Ocean in the East Kunlun domain could be traced back at least to the early Ediacaran.

Neoproterozoic W[sbnd]Sn mineralization in the western Jiangnan Orogen, South China: Insights from the Fanjingshan S-type granites

The Jiangnan Orogen boasts abundant Neoproterozoic granitoids alongside locally significant WSn mineralization in South China. However, the factors governing the relationships between granites and the WSn mineralization remain elusive. Notably, Neoproterozoic WSn mineralization locally occurred within the western margin of the Jiangnan Orogen, encompassing important deposits like the Jiumao, Baotan and Heiwanhe deposits. The W-Sn-bearing tourmaline muscovite (Taoshulin) granite intruded into Neoproterozoic Fanjingshan Group, comprising of low-degree metamorphosed sedimentary rocks that locally contain granitic gravel (two-mica granite). These granites in this study have high SiO2 (73.6–77.4 wt%), Al2O3 (12.8–15.1 wt%), Na2O (3.16–5.25 wt%) and high A/CNK values (1.28–1.47), which display co-variation trends. They have extremely low rare earth element (REE) concentrations (< 35 ppm) and exhibit rare earth element (REE) patterns characterized by strong negative Eu anomalies (< 0.28), implying highly fractional crystallization. Zircon and apatite LA-ICP-MS UPb dating reveal that the emplacement of the Taoshulin tourmaline muscovite granite occurred around 830 Ma, similar to the UPb age (835 ± 7 Ma) of cassiterite, establishing the clear temporal-genetic relationship between granites and WSn mineralization. The zircon UPb age of 847 ± 14 Ma and the apatite UPb age of 852 ± 7 Ma obtained from the two-mica granite likely indicate a ca. 850 Ma granitic magmatism event. These two-episode granites exhibit negative εHf(t) values (+0.9 to −8.0), corresponding to two-stage Hf model ages of 1.7 to 2.2 Ga, indicating their derivation from Paleoproterozoic metasedimentary basement rocks. It is noteworthy that the W-Sn-bearing granite has high tetrad effect (TE1,3 = 1.16–1.24) and very low Nb/Ta ratios (mostly bellow four) that may have resulted from magmatic-hydrothermal alteration. Moreover, the ca. 830 Ma W-Sn-bearing granite is characterized by a notable concentration of high fluorine, distinctively negative Eu anomalies, and non-chondritic REE behavior in apatite. Hence, the WSn mineralization in the Fanjingshan region was probably constrained by various factors, including source materials, magmatic processes, physicochemical conditions and magmatic-hydrothermal processes. Our findings highlight the pivotal role played by Neoproterozoic muscovite tourmaline granites as hosts for WSn mineralization in the Fanjingshan region. In summary, this study emphasizes the significance of the ca. 830 Ma highly differentiated S-type granites holding significant potential for the exploration of critical metals such as W, Sn, Nb, and Ta in the western part of the Jiangnan Orogen and in geologically analogous regions across the globe.

Petrogenesis of the > 2.90 Ga komatiite in the Sujiagou region of the North China Craton: Implications for Archean mantle source and geodynamic setting

Komatiite, characterized by high MgO content and low H2O concentration, is crucial to understanding the Archean magma processes and crust–mantle differentiation. Although well preserved in most cratons, Archean komatiites are scarce in the North China Craton (NCC). The Sujiagou komatiites, as the most typical Archean komatiites in China, were exposed in the Luxi terrane, but their geochronology and petrogenesis types remain controversial. In this study, our new Re–Os data indicate the Sujiagou komatiites originated before 2.90 Ga. The felsic zircons discovered in the komatiites, coupled with Nb–Th–La simulation, suggest ∼ 2 % crustal contamination of the komatiites. Thus, the least-altered, spinifex- and massive-texture samples that underwent unconspicuous crustal contamination were selected as proximate proxies for the primary magma composition. The Al/Ti ratios of the Sujiagou komatiites are comparable to or slightly exceed those of chondrite, suggesting they were aluminium-undepleted komatiites and formed at ∼ 8 GPa. The primitive mantle-normalized rare earth element (REE) patterns show depleted light REE and flat heavy REE, suggesting approximately 50 % partial melting based on REE simulation. Additionally, the komatiites exhibit slightly depleted Os isotope ratios, with an average γOs(t) value of -0.3, indicating the magma source is comparable to or slightly depleted to chondrite. Simulation of the relevant Nb/Zr and La/SmPM ratios further suggests the mantle source became slightly depleted due to ca. 1 % melt extraction. Furthermore, the Mg isotopic composition of the Sujiagou komatiites (δ26Mg = -0.23 ± 0.03 ‰) is consistent with that of the primitive mantle, indicating the absence of recycled carbonate material in the mantle source. Both Re–Os and Mg isotopes reveal limited involvement of crustal or carbonate material in the mantle source, implying the absence of oceanic slab subduction in the Luxi terrane during this time. The formation of the Sujiagou komatiites can be attributed to a hot mantle plume, resulting from high potential and eruption temperature. The identification of felsic zircons in the Sujiagou komatiites indicates the presence of an ancient continental nucleus in the Luxi terrane. Combined with the spatially adjacent terrigenous clastic sedimentary rocks, we suggest that the Sujiagou komatiites erupted most likely in a continental margin of the old terrane.

Genetic Type and Formation Evolution of Mantle-Derived Olivine in Ultramafic Xenolith of Damaping Basalt, Northern North China Block

Olivine in deep-seated ultramafic xenoliths beneath the North China Block serves as a crucial proxy for decoding the compositions, properties, and evolution of the lithospheric mantle. Here, we conduct an investigation on olivine (including gem-grade) hosted in ultramafic xenoliths from Damaping basalt in the northern part of the North China Block. This contribution presents the results from petrographic, Raman spectroscopic, and major and trace elemental studies of olivine, with the aim of characterising the formation environment and genetic type of the olivine. The analysed olivine samples are characterised by high Mg# values (close to 91%) possessing refractory to fertile features and doublet bands with unit Raman spectra beams of 822 and 853 cm−1, which are indicative of a forsterite signature. Major and trace geochemistry of olivine indicates the presence of mantle xenolith olivine. All the analytical olivine assays ≤0.1 wt % CaO, ~40 wt % SiO2, and ≤0.05 wt % Al2O3. Furthermore, olivine displays significantly different concentrations of Ti, Y, Sc, V, Co, and Ni. The Ni/Co values in olivine range from 21.21 to 22.98, indicating that the crystallisation differentiation of basic magma relates to oceanic crust recycling. The V/Sc values in mantle/xenolith olivine vary from 0.54 to 2.64, indicating a more oxidised state of the mantle. Rare earth element (REE) patterns show that the LREEs and HREEs of olivine host obviously differentiated characteristics. The HREE enrichments of olivine and the LREE depletion of clinopyroxene further assert that the mantle in the Damaping area underwent partial melting. The wide variations of Mg# values in olivine and the Cr# values in clinopyroxene, along with major element geochemistry indicate transitional characteristics of different peridotite xenoliths. This is possibly indicative of a newly accreted lithospheric mantle interaction with an old lithospheric mantle at the time of the basaltic eruption during the Paleozoic to Cenozoic.

Volcanic-intrusive connections and crystal-melt segregation in the Dulan tilted crustal section: Insights from accessory mineral evolution

The volcanic-intrusive connection is critical for understanding the formation of transcrustal magma systems and the mechanisms driving magma eruption. Yet, the genetic links between abyssal intrusive rocks and acidic volcanic rocks remain poorly understood. Here, we present new data from the Dulan volcanic-intrusive complex, a tilted section of the East Kunlun orogenic belt, integrating zircon UPb dating, trace elements, apatite and zircon Hf isotope geochemistry, and whole-rock geochemistry to investigate volcanic-intrusive connections and track crystal-melt segregation processes. The Dulan complex comprises rhyolite, granite porphyry, and granodiorite, all showing consistent zircon UPb ages, rare earth element (REE) patterns, and εHf(t) values, suggesting a shared magma source. Glomerocrysts of plagioclase, alkali feldspar, and hornblende, along with antecrystic zircon and apatite, imply a cumulate affinity in granodiorite and granite porphyry. Compositional variations in whole-rock and accessory minerals indicate that plagioclase, apatite, and zircon fractionation significantly influenced magma evolution. We propose a two-stage crystal segregation process in a ∼ 2 Myr-long magma reservoir system. In the early stage, at ∼33 km depth, aqueous fluid influx initiated crystal-melt segregation, forming the Dulan granodiorite from residual mush. In the later stage, mafic melt and fluid injections caused crystal-melt segregation in a shallower reservoir at ∼12 km depth, with high-silica magma producing rhyolite, while residual mush consolidated into granite porphyry. Our findings suggest that volcanic-intrusive connections are more complex than mere compositional equivalence or complementarity, requiring multidimensional analysis through accessory minerals and whole-rock geochemistry.

REGENERATION OF THE DESIGN OF WEAVING AND EMBROIDERY PATTERNS BASED ON ARTIFICIAL INTELLIGENCE TECHNOLOGIES

Purpose of this work is to determine the feasibility of using AIGC (Artificial Intelligence Generated Content) technology to restore the design of traditional Yao patterns in order to protect and preserve the culture of the Yao ethnic group, and at the same time contribute to the modernization of the application of traditional arts. Methodology: In this study, based on the classification and combing through Yao weaving and embroidery patterns through literature research, the two selected design patterns are coded and extracted, and AIGC (Artificial Intelligence Generated Automatic Generation Contents) technology is cited to carry out regeneration design of the patterns. Results: By studying the process of creation and evolution of Yao patterns, it was found that its unique cultural and aesthetic value warrants study and preservation. It was found that patterns created using AIGC technology not only retain the basic elements of traditional patterns, but also introduce various design innovations. These newly created templates have a high visual aesthetic and can be applied to the design of Yao derivative cultures. Scientific novelty of the study consists in the identification of the main characteristics of the traditional patterns of the Yao people, and the proposed approach to their preservation and integration into modern design. By overcoming the limitations of traditional design, this study combines AIGC technology with national traditional culture. Practical significance: This study is of great scientific significance because it not only provides a new method for digital preservation and innovative design of Yao patterns, but also contributes to the study of the application of artificial intelligence in pattern innovation. Research materials can be used both in educational courses and in project design practices.

The partitioning of chalcophile and siderophile elements (CSEs) between sulfide liquid and carbonated melt

Carbonated melts play a significant role in mobilizing lithophile and volatile elements in the Earth’s mantle and mantle metasomatism. However, there has been limited investigation into their potential for mobilizing chalcophile and siderophile elements(CSEs). In this study, we experimentally determine the sulfide liquid–carbonated melt partition coefficients of CSEs (DCSESul/C_melt) for a range of elements, including Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, In, Sn, Re, and Pb, at 1300–1600 °C, 1.0–3.0 GPa, andoxygen fugacity (fO2) close to the graphite-CO2 fluid buffer. Furthermore, the DSul/C_melt values for lithophile elements Cr, Mn, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, and Ta (DLithoESul/C_melt) are also determined. The obtained DCSESul/C_melt values are 34–1230 for Co, 380–75200 for Ni, 200–14900 for Cu and Ag, 0.5–28 for Zn and Mo, 42–98 for Se, 24–640 for Cd, 5–52 for In and Sn, 650–15200 for Re, and 22–2470 for Pb. The obtained DLithoESul/C_melt values are below 1–10. The variations of DCSESul/C_melt and DLithoESul/C_melt are primarily influenced by the FeOtot content in the carbonated melts. A partitioning model was developed to parameterize DCSESul/C_melt and DLithoESul/C_melt as a multi-function of pressure, temperature, composition of the carbonated melt (mainly the FeOtot content), and composition of the sulfide liquid. Our parameterization can explain the observed large variations of DCSESul/C_melt and DLithoESul/C_melt for most of the trace elements studied. Using our DCSESul/C_melt parameterization, we model the CSE and U–Th contents of low-degree partial melts of carbonated mantle peridotite and slab eclogite with sulfur concentrations ranging from 50 to 500 µg/g. The modeling results can generally explain the trace element patterns observed in natural kimberlites and carbonatites; however, the peridotite- or slab-derived carbonated melts have a low capability in mobilizing CSEs, which can extract less than 3 % of Cu, Ni, Co, Re, and Os, 3–30 % of Mo, Pb, and Se, but up to 30–50 % U and Th from the source lithology. Consequently, the influence of carbonatite metasomatism on the Cu, Ni, Co, Re, and Os systematics of the Earth’s mantle is minimal, although local enrichments of CSEs may occur when sulfides precipitate from carbonated melts. Because of the elevated concentrations of U and Th and the corresponding U/Pb and Th/Pb ratios in the carbonated melts, the mantle lithology that has undergone metasomatism by these melts can become a geochemical reservoir with high 208Pb/206Pb ratios. However, the effect of carbonatite metasomatism on Re–Os isotopic systems of the mantle is minimal due to the low Re concentrations in the carbonated melts. Accordingly, the radiogenic Pb–Os isotopic signatures of HIMU ocean island basalts cannot be explained solely by carbonatite metasomatism in the mantle.

A slope-based J-integral approach and advanced image processing for assessment of the cyclic fatigue delamination behavior of adhesive joints

A fatigue fracture mechanics methodology was developed and established, employing a slope-based J-integral approach combined with advanced image processing techniques. Adhesively bonded double cantilever beam (DCB) specimens were tested under constant displacement amplitude loading. The beam rotation was tracked by affixing a repetitive pattern on the DCB specimens and capturing images at the maximum displacement amplitude. Using a custom-developed image processing procedure, the beam rotation was deduced. To validate the methodology, DCB fatigue experiments were conducted at 23, 60 and 75 °C on aluminum adherends bonded with a structural 2-K epoxy adhesive. The J-based approach was compared with a conventional, compliance-based linear elastic fracture mechanics (LEFM) method. The epoxy was a rather brittle, high-modulus adhesive with a bond line thickness of 0.25 mm, resulting in predominantly linear elastic material behavior. By analyzing the images taken during fatigue testing, a stiffening effect of the steel load blocks was observed. Excluding pattern elements directly below the load block yielded the best agreement between J-integral and LEFM data. Both approaches were in excellent agreement within the investigated temperature range. The investigated adhesive exhibited a highly temperature-dependent behavior, which was associated with higher crack propagation rates and a lower fatigue threshold at 60 and 75 °C.

Scheelite texture and composition fingerprint skarn mineralization of the giant Yuku Mo-W deposit, Central China

Scheelite is widely used to reveal ore-forming redox environments and track hydrothermal evolution processes in W-bearing deposits. Yuku, situated in Central China, is a typical skarn Mo-W deposit discovered recently in the Luanchuan Mo-W-Zn-Pb ore district. This study determined the compositions of the Yuku scheelite via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and electron microprobe analysis (EMPA) techniques. Based on the textural characteristics and mineral assemblages, three types of scheelite were categorized, including Sch A1, Sch A2, and Sch B. In general, Sch A1 formed during the prograde stage, mostly occurring as euhedral grains that distributed discretely within the interstices of skarn minerals. Sch A2 predominantly formed as the rim of Sch A1 or crosscut Sch A1. It is commonly associated with sulfides, such as pyrrhotite, pyrite, and molybdenite. Sch B is primarily observed in the quartz-sulfide veins or within pyrrhotite crystals, occurring later than Sch A1 and Sch A2. Geochemically, Sch A1 contains a significantly higher Mo content (>14,300 ppm) and is characterized by a negative inclined chondrite-normalized rare earth element (REE) pattern, while Sch B has Mo contents lower than 10,300 ppm and exhibits an M-type tetrad REE pattern. Sch A2 contains a Mo content ranging from 146 ppm to 89,000 ppm (mean 27,900 ppm) and displays an intricate REE pattern that partially overlaps with Sch A1 and Sch B. The difference of REE concentrations among different scheelite generations is controlled by substitution mechanisms and also influenced by the precipitation of garnet and pyroxene. Sch A1 and Sch B exhibit a linear 1:1 trend between Na (atom) and ΣREE – Eu + Y (atom), indicating the important role of substitution via 2Ca2+ = REE3+ + Na+. The concentrations of Nb, Ta and V are notably low, supporting only a small amount of REE incorporation into Sch A1 through Ca2+ + W6+ = REE3+ + (Nb + Ta + V)5+. The REE patterns of Sch A1 and partly Sch A2 resemble those of the causative intrusions, indicating that substituting the site vacancy in scheelite lattice is another crucial mechanism. All three substitution mechanisms play roles in REE incorporation during the scheelite mineralization process. Negative Eu anomalies prevail in Yuku scheelite (mean δEu = 0.77), although positive Eu anomalies are also observed, particularly in Sch B (mean δEu = 1.11). Additionally, there is a conspicuous decreasing trend in the Mo content from the prograde to late stage, suggesting that the Mo-W mineralization at Yuku likely experienced a decrease in oxygen fugacity and/or temperature. Furthermore, in a comparative analysis of scheelite Mo content and Eu anomaly with other deposits, it was observed that Mo content in skarn deposits is generally higher than that in orogenic deposits (mostly <100 ppm), providing a tool for distinguishing deposit types utilizing scheelite geochemical characteristics.

Application of symbolic language and pattern innovation of Chaoshan peach cake mold in paper packaging design

To explore the symbolic language of the Chaoshan peach cake mold and its innovative applications in modern design, the material form and cultural connotations of the mold patterns were analyzed from a semiotic perspective. Through a symbolic language of the primary pattern elements, the essence of the traditional culture they embody was revealed. Building on this analysis, the generative rules of shape grammar were applied to creatively reinterpret and recombine these traditional pattern elements, resulting in a set of innovative designs that retain the essence of traditional culture while incorporating modern design aesthetics. Furthermore, these innovative patterns were implemented in paper packaging design, and their effectiveness was validated through product evaluation. Through an in-depth exploration and innovative application of the symbolic language of the Chaoshan peach cake mold, a successful fusion of traditional cultural symbols and contemporary design concepts was achieved. This approach provides a new pathway for the inheritance and innovation of Chaoshan peach cake mold culture and offers insights into the modern transformation of other traditional cultures.

Petrological relationships between plutonic and volcanic rocks in a continental volcanic arc system: Evidence from plutonic xenoliths in the Sierra de Pachuca, Mexico

Relatively abundant plutonic xenoliths found in some lava domes, lava flows, and scoria cone deposits were employed to study the features and processes between the magmatic plumbing systems and volcanic rocks in the Sierra de Pachuca, central-eastern Mexico. We present petrographic, geochemical, isotopic data and five U-Pb ages for some plutonic xenoliths and the Sierra de Pachuca host rocks to provide evidence of magmatic processes existing under this volcanic range. The phaneritic plutonic xenoliths were grouped into six lithological types based on petrography, chemical data, and isotopic ages. Four types (A to D) are hosted by the El Ventoso lava dome. Their compositions span from calc-alkaline gabbro to granite, with U-Pb zircon ages ranging from 23.1 ± 1.4 to 21.6 ± 0.6 Ma. These ages are contemporaneous with the emplacement of rhyolitic ignimbrites found at the base of the Sierra de Pachuca (22.8 ± 0.5 Ma U-Pb zircon age). The trace element patterns for these Late Oligocene-Early Miocene plutonic xenoliths display enrichment of LILE relative to HFSE and enrichment of LREE respecting to HREE typical of subduction-related rocks. Negative P, Ti, and Eu anomalies in these patterns also suggest fractional crystallization processes in magmas that produced the A to D types. Two more types of plutonic xenoliths (E and F) display gabbro and syenite compositions, respectively, and are hosted by the San Miguel-Santa María Regla columnar jointed basalts (gabbro samples) and by the El Prieto scoria cone (syenite samples). Based on one U-Pb zircon age (2.4 ± 0.2 Ma) and geological correlations, these plutonic xenoliths and their host rocks were emplaced in the Quaternary. They exhibit alkaline compositions, and their trace element patterns indicate an enriched mantle source with positive Ba and Pb anomalies, not typical of subduction-related magmas. The isotopic values (87Sr/86Sr = 0.70390 to 0.70502 and εNd = −2.99 to +0.76) for the Late Oligocene-Early Miocene A to D types and host rocks suggest the interaction of magmas with continental crust components. In contrast, the Quaternary xenoliths of E and F types and their host rocks display isotopic data (87Sr/86Sr = 0.70396 to 0.70602 and εNd = +0.13 to +3.66) that evidence of less interaction with continental crust components. In all studied xenoliths, the Pb isotopic ratios (206Pb/204Pb = 18.60–18.87; 207Pb/204Pb = 15.57–15.63 and 208Pb/204Pb = 38.39–38.68) lie on a mixing line between a mantle-like member and a radiogenic component such as the Paleozoic Acatlán complex that probably underlie the Sierra de Pachuca area. Based on the results obtained, it is proposed that the Late Oligocene-Early Miocene A to D type xenoliths represent the plumbing systems from which the volcanic rocks of the Sierra de Pachuca were extruded. On the other hand, the E and F types also represent the roots or magmatic reservoirs from which the Quaternary lava flows and scoria cones, located in the rear-arc part of the active front of the Trans-Mexican Volcanic Belt, were formed. Additionally, these two types of xenoliths and their Quaternary host rocks have hybrid geochemical characteristics of alkaline magmas influenced by crustal components produced during a slab rollback stage.

Determination of Geochemical Background and Baseline and Research on Geochemical Zoning in the Desert and Sandy Areas of China

Resources in deserts and sandy landscapes have potential for development, but existing surveys and sampling have not collected desert soil samples. As such, the geochemical background of these spaces remains unexplored due to the vastness and desolation of deserts. Therefore, researching the geochemical background values and geochemical baseline values of deserts is of long-term significance. Our research indicates that in addition to macrostructural environmental divisions, microelement geochemistry can also be used for geological unit zoning. In this paper, geochemical background and geochemical baseline values of 61 desert elements were calculated using the iterative method, frequency histograms method, and multifractal concentration-area method. It also analyzes the distribution characteristics of major, trace, and rare earth elements, and divides the 12 desert sand regions into different geochemical zones. This paper determines, for the first time, the geochemical background values of elements in Chinese deserts, filling the gap in the study of desert background values. By combining machine learning methods, different deserts have been divided into three geochemical zones. This research will greatly enhance our ability to interpret the geochemical distribution and evolutionary patterns of desert elements in China, and it has important scientific significance and practical value for desert research.

Transcriptional dynamics and tissue-specific expression patterns of transposable elements in orthopteran insects

Transposable elements (TEs) are prevalent in the genomes of orthopteran insects, contributing significantly to their genome evolution and diversity. In light of the existing gap in our understanding of TEs transcript dynamics in orthopteran insects, we recognize the critical need to undertake comprehensive analyses in this area. Therefore, we have decided to delve into the characterization of TE transcripts, their abundance profiles, and the formation of chimeric transcripts using RNA-seq data and genome assemblies. The transcript analysis of TEs across various species revealed significant differences in TE abundance and expression patterns. In particular, Schistocerca americana exhibited twice the number of transcripts within the genus Schistocerca compared to the average of other species, while Gryllus bimaculatus displayed the lowest number of transcripts. Despite this, all Schistocerca species shared similar fractions of TE transcripts at the clade level, with DNA transposons (45%) being the most abundant, followed by LINE (19%) and LTR elements (18%). Interestingly, Acrida cinerea displayed different TE abundance patterns compared to Schistocerca species, particularly with an increased proportion of LTR transcripts, accounting for 31% of the total transcripts. Further analysis revealed tissue-specific transcriptional activity of TE clades, with notable differences between male and female specimens. In Gryllus bimaculatus, TEs were highly transcribed across ovaries and gut tissues in females compared to male testes and gut. Conversely, Gastrimargus marmoratus displayed higher TE transcription in male tissues compared to females, indicating species-specific expression patterns. A similar pattern has been observed in Acrida cinerea, except in female gonads, where 4618 TEs were transcribed compared to 3757 in male gonads. Despite these variations, no correlation was found between genome size and TE transcript abundance. Additionally, highly conserved TEs were involved in the formation of chimeric transcripts, indicating potential regulatory roles in gene expression. The expression quantification analysis of chimeric TEs and genes revealed tissue-specific expression patterns, and TEs do not control the overall expression of all genes except some, suggesting regulatory roles of TEs in gene expression. Overall, our study underscores tissue-specific variations in TE expression and transcript abundance among different species. Additionally, our findings suggest the involvement of highly conserved TEs in the formation of chimeric transcripts across different species.

Jurassic magmatism in the Garzón region of the Colombian Andes: insights from whole-rock geochemistry and zircon isotope analysis of granites and subvolcanic rocks

ABSTRACT New whole-rock geochemical and zircon U – Pb dating and Lu – Hf isotope data are presented for the Garzón granites and related subvolcanic rocks, which formed during widespread Jurassic arc magmatism in the Colombian Andes. This magmatism resulted from the subduction of a proto-Pacific plate under the NW South American margin. Our data indicate that the granitic and related rocks of the Algeciras, Altamira, and Sombrerillo Plutonic Massifs in the Garzón region have crystallization ages ranging from 179 to 169 Ma. These rocks are characterized as high-K alkali-calcic or calc-alkaline, magnesian, with 0.66 ≤ Fe# ≤ 0.94, and metaluminous to slightly peraluminous, with 0.67 ≤ ASI ≤ 1.01, exhibiting geochemical signatures. The trace element patterns normalized to MORB reveal pronounced negative anomalies for Nb, P, and Ti, alongside positive anomalies for Pb, Rb, Sr, Y, Zr, and Ba. The REE patterns display strong LREE fractionation over HREEs, with moderate to absent negative Eu anomalies in mafic to intermediate rocks (0.5 ≤ Eu/Eu* ≤ 1.0) and greater significance in felsic rocks (Eu/Eu* up to 0.6). Most granitic rocks display negative εHf(t)-in-zircon values (−7.7 to −1.2), indicating substantial contributions from ancient continental crust. In contrast, the subvolcanic rocks have a mix of positive and negative εHf(t) values (from −7.9 to + 11.5), reflecting significant input from both juvenile mantle and ancient crustal sources (221 Ma ≤ TDM ≤1516 Ma). After 167 Ma, the magmatic activity diminished and ceased in the Garzón region, while it continued to the west in the Central Cordillera until ca. 129–110 Ma, with a gradual increase in contributions from the mantle, as indicated by systematic zircon Hf isotopes, arguably due to changes in the subduction regimes.

Triple-Stacked FET Distributed Power Amplifier Using 28 nm CMOS Process

A broadband 28 nm complementary metal–oxide–semiconductor (CMOS) power amplifier was implemented using a distributed amplification design. To develop a model library for high-frequency design, various test patterns for active and passive elements were fabricated and compared through measurements. As a result, a symmetrical n-channel field-effect transistor (NFET) was used as the active device, and a co-planar waveguide (CPW) with floating bottom metal layers was chosen as the transmission line for the passive element. These choices demonstrated superior radio frequency (RF) characteristics at high frequencies compared to other device candidates. Furthermore, to address the low breakdown voltage of CMOS, a triple-stacked FET structure was designed as the gain cell of the distributed power amplifier (DPA). The fabricated DPA showed a maximum small-signal gain of 22 dB and a minimum of 10 dB from DC to 56 GHz, with a maximum saturated output power of 20 dBm and a minimum of 13 dBm from 1 to 39 GHz. Notably, these results were achieved on the first attempt by designing solely based on measurement data from the test patterns.

A Near‐Zero Index Metamaterial Lens for Reduced Complexity and High‐Performance Active Electronically Scanned Arrays

AbstractA lens consisting of an anisotropic near‐zero index metamaterial (NZIM) is introduced for improving the far‐field performance of active electronically scanned arrays (AESA). Several simulation studies demonstrate how the NZIM lens (metalens) can be functionalized to transform the embedded element pattern of an array from a typical cosinusoidal shape to a flat‐topped pattern, dramatically reducing the gain at wider angles. This corresponds to reductions in scan loss and suppression of grating lobes in the desired field of view (FOV), especially for arrays with large element spacing (i.e., sparse or thinned arrays). The metalens concept is demonstrated through several simulation studies illustrating the beam shaping capability of NZIM materials. A fabricated metalens demonstrates full suppression of grating lobes and minimal scan loss with a ±10° FOV, which is ideally suited for limited FOV applications such as geosynchronous satellite communications.

Prospecting potential evaluation based on geological factor analysis-a case study of Jiaojiacheng ore belt

Mineral forecasting is of great significance for social development. As an important aspect of geological exploration, its importance lies not only in its direct contribution to economic growth but also in how it employs precise technical methods for mineral exploration. This study utilizes a geological factor analysis method that combines various complex geological observation factors into a few dominant comprehensive factors, followed by causal research and multivariate statistical analysis for classification. Based on this, the study applies principles and methods of elemental geochemistry to identify the dispersion and concentration patterns of associated elements from the distribution characteristics of ordered accompanying factors, providing a scientific basis for mineralization forecasting. Using geochemical experimental data, geological survey comprehensive profiles, and factor score contour maps, this paper analyzes the southern extension segment of the Jiaojia gold mine mineralization belt through geological factor analysis. It was found that the anomalous distribution of chemical elements F4 (Hg, Au, Pb) exhibits certain regularities, which significantly indicate mineralization information and suggest the presence of two main longitudinal mineralization belts.

Rare earth element patterns in sediments from the Great Lakes basin

This study presents a comprehensive analysis of rare earth element (REE) concentrations in >100 sediment samples from Lakes Erie and Huron, two of the North American Great Lakes. Significant intra- and inter-lake variability in REE concentrations is observed for both lakes Erie and Huron (<10 μg/g < versus <6 mg/g ƩREE, respectively). Light (L) REE were enriched over heavy (H) REE in surface sediment samples across both lakes, particularly in the North Channel of Lake Huron. Sediment cores from both lakes contained REE concentrations that are equally variable over time and correlated with major elements and other trace metals, reflective of the strong control of sediment accumulation rates on REE concentrations. Sequential extractions show that REE are predominantly associated with the residual (silicate) fraction (>50%) and likely originated from geogenic sources (basin weathering). However, considerable REE fractions (up to 16%) were also associated with oxide, phosphate minerals and organic/reducible material, particularly for the LREE. We attribute this apportionment and LREE enrichment to aqueous complexation and export from the water column. Finally, REE normalization and pattern-fitting reveal positive Ce anomalies (up to 16.2) in specific locations that could be indicative of hypolimnic redox gradients, whereas minor Gd and Eu anomalies (0.9 for Eu, and 1.02 for Gd, on average) likely relate to the parent rock signature. Our findings contribute valuable baseline data and insights into the complex interplay of geological, hydrodynamic, and environmental factors influencing REE distribution patterns in these lake sediments.

Petrography and geochemistry of volcanic rocks of the Kulf-Amba area, in the Northwestern Ethiopian plateau: Implication for petrogenesis of felsic volcanic suites

The Kulf-Amba area, located on the Northwestern Ethiopian plateau, is primarily composed of Cenozoic volcanic rocks with minor intertrappean sediments. To understand the petrogenesis of these rocks, we conducted field investigations, petrographic studies, and geochemical analyses. The main volcanic products include basalt (upper and lower), rhyolite lava flows, rhyolitic ignimbrite, volcanic glass, and agglomeratic tuff. Basalts exhibit aphanitic, porphyritic, and glomerophyric textures, with phenocryst of olivine, Ca-rich plagioclase, clinopyroxene, and Fe-Ti oxides. Felsic rocks display porphyritic, aphyric, and glassy textures, with phenocryst of quartz, alkali feldspar, and Fe-Ti oxides. Geochemical data reveal a bimodal composition. The mafic rocks resemble high titaniferous (HT2) basalts of Northwestern Ethiopia and are classified as transitional to tholeiitic. Felsic rocks are primarily peralkaline comendites. The mafic rocks exhibit a depleted heavy rare earth element (HREE) pattern with (Dy/Yb)N = 1.75–2.02 and enriched light rare earth element (LREE) values with (Ce/Yb)N = 7.16–9.26, without a significant negative Eu anomaly. Enrichment in LREE with (Ce/Yb)N = 6.27–15.03 and flat HREE with (Dy/Yb)N = 1.23–1.79, with varying Eu negative anomaly are characteristics of the felsic volcanic rocks, indicating removal of plagioclase throughout their evolutionary process. The consistent Nb/Ta (17.29–23.67 ppm) and Zr/Hf (37.53–45.08 ppm) ratios in both mafic and felsic rocks suggest that fractional crystallization was the dominant process in their formation, with small crystal contamination. The primitive mantle-normalized variation diagram for the mafic rocks reveals LREE enrichment and HREE depletion, indicating garnet in the source. Melting models using primitive mantle normalized values of Sm/Yb vs. La/Sm ratios further confirm garnet's presence and suggest a low degree (2%) of partial melting a source with less than 2% of garnet. The trace element signatures and geochemical modelling of the mafic lavas indicate a plume-related origin, potentially related to the Afar mantle plume.

Nanotube formation and coating of hydroxyapatite-polyvinyl alcohol-collagen composite on Ti-6Al-4V metal alloy

Abstract Ti-6Al-4V metal is widely used as an implantable material due to its biocompatibility and corrosion resistance; however, it has low bioactive properties. The formation of nanotubes and a hydroxyapatite-polyvinyl alcohol-collagen composite coating on Ti-6Al-4V metal aims to enhance its biocompatibility and bioactivity. The nanotube oxide layer Ti-6Al-4V was formed by the anodization method. The composite’s infrared spectrum showed characteristic absorption bands from Hydroxyapatite (HAp), polyvinyl alcohol, and collagen. The composite-coated Ti-6Al-4V metal, both non-nanotube, and nanotube, showed a typical diffraction pattern of HAp and titanium element. The electron microscope image showed the uniform granular form of HAp. The corrosion test results showed that composite-coated nanotube Ti-6Al-4V metal could not improve corrosion resistance. It is also relevant to the in vitro test in a lactate ringer solution that showed the higher Ca2+ ion of nanotube Ti-6Al-4V metal than that of non-nanotube Ti-6Al-4V metal.